Hi, I want to create some refcounted objects using shared_ptr. For example if I have class A_impl, I want my users only to use A. So, I created the following code: class A_impl { public: virtual ~A_impl () {}; void dosomething () {}; }; typedef shared_ptr <A_impl> A; The challenge is now that I want to provide some typedefs on A (which is a shared_ptr()). So that my users can use: A::my_value_type; I am aware of the reference_type, but I need to have some additonal typedefs and constants as part of A. I have started with a partial template specialization of shared_ptr, but I have my doubts whether this is the correct way. Another option would be to create our own shared_ptr that just embeds the boost_shared_ptr and exposes just some of its methods. Any specific ideas on this? Regards, Johnny